# Adding an Expansion Hub

If you want to use more than 4 motors or 6 servos, you can add an Expansion Hub to your robot. An Expansion Hub ([REV-31-1153](https://www.revrobotics.com/rev-31-1153/)) can be added to a Control Hub ([REV-31-1595](https://www.revrobotics.com/rev-31-1595/)) or another Expansion Hub. The Expansion Hub has all of the same ports as the Control Hub but without the wireless capability.&#x20;

### Control Hub vs Expansion Hub in FIRST

| **FIRST Tech Challenge**                                                                                                                                                               | **FIRST Global**                                                                                                                                                 |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| FIRST Tech Challenge teams may use one (1) Control Hub and may add one (1) Expansion Hub starting in the 2020-2021 season. Read the official FTC Game Manuals for complete game rules. | FIRST Global teams must use one (1) Control Hub and may add one (1) Expansion Hub to their robot. Read the official FIRST Global manual for complete game rules. |

{% hint style="warning" %}
If you are using a configuration file from a 5.5 or earlier version of the Robot Controller Application, you will need to create a new configuration file.&#x20;
{% endhint %}

### Adding an Expansion Hub to your Robot

| Step                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            | Image                                                                                                                                                                                                                                                                                                  |
| --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| <p>Use the XT Extension Cable to connect power between the Control Hub and the Expansion Hub.</p><p><br>Use a 3-pin JST PH cable to connect the RS485 port on the Control Hub to the Expansion Hub.</p>                                                                                                                                                                                                                                                                                                                                                         | ![C:\Users\Rachel\AppData\Local\Microsoft\Windows\INetCache\Content.Word\text11874-5-0-4-7-5-6.png](https://1359443677-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2Fftc-control-system%2F-M8MwLCHioGUmBeHgdmq%2F-M8N18g7FA00YUtTVAaT%2F38.png?generation=1590614867952389\&alt=media) |
| From the Driver Station choose “Configure Robot”                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | ![](https://1359443677-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M4_pJHI8HTuZFQTNfcy%2F-MMMGYArvgF-v8USDpsj%2F-MMNGZJskI9MIK4ZTzXe%2FConfiguration%20Menu.png?alt=media\&token=94825df3-c05c-4770-a3a7-8eb0da74fd1d)                                                              |
| Select “New” in the top left hand corner.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | ![](https://1359443677-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M4_pJHI8HTuZFQTNfcy%2F-MMMGYArvgF-v8USDpsj%2F-MMNK7LRGBCDiRL3s-b-%2FNew%20Config.svg?alt=media\&token=d238a3a1-bc4c-4bd5-9a79-cb6cad48f928)                                                                      |
| <p>Select “Control Hub Portal”</p><p></p><p>Note: This will show an Expansion Hub Portal if using an Android Device as a Robot Controller</p>                                                                                                                                                                                                                                                                                                                                                                                                                   | ![Screenshot\_2010-04-11-22-51-34.png](https://1359443677-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M4_pJHI8HTuZFQTNfcy%2F-MMMGYArvgF-v8USDpsj%2F-MMNKAsTg4lc6fjASYSz%2FPortal.svg?alt=media\&token=a05a05c1-522c-4c71-b5d5-154b97320bbc)                                         |
| <p>Now you have two Hubs to choose from. Either the Control Hub or the Expansion Hub.</p><p></p><p>“Expansion Hub 2” is the connected Expansion Hub that is communicating over RS485.<br></p><p>Configure and program as necessary. Please see the <a href="../control-hub-gs/configuration">Configuration</a> section of for an overview of configuration.</p><p></p><p>Note: If using an Android Device as a Robot Controller there will be two Expansion Hubs located here. The Expansion Hub Address may need to change so they do not conflict.</p><p></p> | ![Screenshot\_2010-04-12-00-28-32.png](https://1359443677-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M4_pJHI8HTuZFQTNfcy%2F-MMMGYArvgF-v8USDpsj%2F-MMNKRh9RdbBgK7ulVW5%2FHub%20Selection.svg?alt=media\&token=f94580f3-49f6-4da6-a3be-92d1ae4847d9)                                |
